Improvement in air and gas engines



6 Sheets--Shee t1 G. W. DAIMLER. ir and Gas Engine.

atented Oct. 11,1875.

[/IIIIII/I N.PETER8, PNOTO-LITNOQRAFHER, WASHINGTON D. C-

6 Sheets--Sheet 2. G. W. DAIMLER. Air and Gas Engine.

Patented Oct. 11,1875.

NPETEHS. PHOTO-LITHOGRAPHER, WASHlNGTO D C.

6 Sheets--S heet 4.

G. W. DAIMLER Air and Gas Engine.

Patented Oct. 11 1875;

NVPEIERS. PHOTO-LITHOGRAPNER. WASHINGTON. Dv C.

6Sheets-Sheet 5. G. W. DAIMLER. Air and Gas Engine.

Patented Oct. 11 I875.

N. FEI'ERS, PHOTQLITHOGRAPHER, WASHINGTON, D. C.

m G. W. DAIML Air and Gas E I N0.l68,623.

UNITED STATES PATENT OFFICE.

GOTTLIEB WILHELM DAIMLER, or MUELHEIM-ONTHE-RHINE, GERMANY.

IMPROVEMENT IN AIR AND GAS ENG|NES. l

Specification forming part'of Letters Patent No. 168,623, dated October 1-1, 1875; application filed April 17, 11575. 7 i

To all whom it may concern Be it known that I, GOTTLIEB, WVILH LM My invention relates to that class of engines wherein, by the explosion of a mixture of combustible gas or hydrocarbon vapor and air inside a cylinder, a loose piston is propelled without doing work, so as, by the expansion and cooling'of the products of combustion, to produce a partial vacuum in the cylinder, thereby causing a working piston to be propelled by atmospheric pressure.

Such a construction of engine is described in the specification to British patents granted to It. A. Brooman, dated 24th August, 1863, No. 2,098, and to F. W. Wenham, dated 9th May, 1804, No. 1,173.

According to my present invention, a waterja-cketed cylinder, open to the atmosphere at both ends, contains. tirst, a working piston;

and, secondly, two other pistons, one on each side of the working piston, which are loose or unconnected, and operate in conjunction with the working piston in the following manner: Assuming the working piston to be at end of back stroke, a charge'o'f gas and air is drawn into a space between it and the front loose piston, and is exploded. The said loose pis ton is thrown by the explosion to the front end of'the cylinder, (without doing wo rk,) Where it is held by means to be hereafter described, whereupon, a partial vacuum being formed in the cylinder by the expansion and cooling otthe gaseous products of combustion, the working piston will, by atmospheric pressure, be caused to perform its forward stroke, the back loose piston-traveling with it; ()n

approaching the front loose piston the back loose pistonis arrested in its motion, while end of the cylinder, and the working piston' performs its back stroke, together with the front loose piston, and the-operation is repeated as above described.

, Thus it will be seen that my improved engine is double-acting, and the reciprocating motion of the working piston may either be utilized directly where reciprocating motion is required, such as in pumping-engines and the 'like; or it may be converted into rotary motion connecting the PlSllOll-lOtl to a crank on an engineshaft. I I will now proceed more particularly to describe theconstruction and mode ofoperating of my improved engine, for which'purpose I shall refer to the accompanying drawings, in which I i Figure 1 shows a longitudinal section of the engine. Fig. 2 shows a plan of the same.

Fig. 3 shows a part sectional plan to an enlarged scale. Fig. I shows a transverse section'o n line X X, Fig. 3; and Figs. 5 to 9 show enlarged details. v p

' The engine as represented on the drawings is supposed to be a horizontal one. It may, however, be arranged in an inclinedor vertical position. The cylinder A, provided with a cold-water jacket, A, is opeuat both ends to the atmosphere, and it is, at each end, somewhat conicallyenlarged, as indicated at A A '13 is the working piston, connected by piston-rod B, cross-head O, and connectingrods D to crank-pins on the fiy-Wheels E E 'on the engine-shaft E. The piston and pistonrod are hollow, and cold water is made to circulate through them by means to be hereafter described. 011 each side of the piston B is a loose piston, F F, the piston-rod '15 being made to work air-tight through a gland, f, provided with packing in the piston F. These loose pistons are of very light construction, consisting, first, of a cylindrical part,f, which carries a broad ring of leather or other mate- :in this position. I

to the atmosphere at their outer sides; but at rial, f acting asa packing, secured at its middle by a metal ring, f so that the pressure existing on one side or the other of the piston tends to press the leather ring against the cylinder in a similar manner to an ordinary cup leather, and thuscauses the piston to work air-tight in the cylinder. The piston consists,

' further, of a coned part, 1, upon which is fitied a loose conical ring, f formed in segments that are held together by a small ring, f fitting-into a groove in all the segments. This segment-ring is connected to springs f, which springs tend to keep the segment-ring at the smallest diameter of the part f*, as shown at Fig. l, in whichcase, the segments being retracted, they allow the" piston to move freely "in "the cylinder. piston'is'propelled by the explosion of the'gas 'andair into the conical enlargement A of the cylinder, and is there suddenly arrested 'by the counter-pressure of the atmosphere, the conical segment-ring f ,-in continuing its for- When, however, the loose ward motion by virtue of its momentum, slides up the conical surface f and, being thus expanded, wedges itself tight between such conical surface and the conical surface of the 'cylinder,as indicated at the righthand end of Fig. 3, and thus the piston F is held securely The pistons F F are open their inner sides they are closed air-tight by vmeans of a curved plate, f strengthened by stays f and formed to the same curvature as the working piston B, so that this can fit close against the loose pistons, as shown. Passing air-tight through the piston B is a rod, G, Fig. 1, with heads at its ends, and capable of sliding'backward and forward through the piston.

This rod, in coming in contact with the loose pistons, keeps these a certain distance apart,

thus causing a charge of gas and air to be drawn in between the working piston and the one loose piston at the end of every stroke, aswill be presently described.

The cylinder A has two ports, H H, for the admission of a charge of gas and air at each end stroke of the working piston, such admission being regulated by valves I I, constructed and operating as will be hereafter. described, and worked' by means of cams or'tappets E on the engine-shaft-E, acting on rods K K,

' connected to the valves.

The'mode in which the engine operates'is as follows: Assuming the working piston B to beat the end of back stroke, resting closely "against the loose piston F, and with a space intervening between it and the second loose "piston F, as shown at Figs.l and3, and assuming, further, that a'charge of gas and air hasbeen admitted into this space through the valve I, and is then ignited, then upon the ex- "plosion taking place the piston F will be rapidly propelled to the front end of the cylinder into the second position thereof. (Shown at theright-hand end of Fig.3.) The gaseous products of'the' explosion being rapidly cooled 'by-their expansion, and by the cooling action of the water-jacket A and the cooled piston and piston rod, a partial Vacuum will be formed in the cylinder, in consequence whereof the motion of the piston F will be arrested when it has arrived at or about the right-hand position shown in Fig. 3, by the counteracting pressure of the external atmosphere. The seg ment-ringf in continuing'its motion, by vir- -tue of its inertia, will wedge the piston F tight in this position, as before explained; and it will be seen that, owing to the conicity of the part A of the cylinder, the piston F will be held in this position, not merely by frictional contact, but by absolute pressure, acting counter to that exerted by the atmosphere. In consequence of the partial vacuum'existing in the cylinder the working piston B and the second loose piston F will now be caused by the external atmospheric pressure to travel together toward the front end of the cylinder,

the packing f ofthe piston F acting in aid.

of the piston B to insure an air-tight contact with the sides of the cylinder. When the piston B has arrived near the end of its forward stroke the rod G, projecting therefrom, in coming in contact with the piston F arrests the motion of the piston F, so that as the working piston continues to advance toward the piston F a space is formed between its back surface and the piston F, and the valve 1 being now opened a charge of gas and air will be drawn into the cylinder between the,

pistons B and F. At the same time the piston B. in approaching the piston F, forces out the condensed products of combustion contained between them through an escape-passage, L, Figs. 1 and 4, provided with a check valve, L. The force of the explosion is so regulated that the piston F, in its fligh t,.is,ar-

rested somewhat short of the full stroke ofthe piston B, so that when the latter comes in contact with the former it pushes it outward from the right-hand position (shown in Fig. 3) up to the extreme end of the cylinderthat is, into the position in which the piston F is shown. By this means the segment-ring f being released from its jammed position, will be caused by the springs f to move into the retracted position shown in the piston F, so that the piston is now loose in the cylinder.

The explosive charge drawn inbetween the pistons B and F being ignited, the piston F is propelled to the back end of the cylinder, where its flightis arrested, as before described with reference 'to F, and the pistons B and F now perform their back stroke, the piston F being arrested by the rod Gr near the end of its stroke, in order to draw in a fresh charge of explosive mixture, and so on. At the extreme end of each stroke the piston B presses the pistons F F slightly against annular buffer-plates M M, held in a yielding manner against the ends of the cylinder by means of bolts passing through lugs A on the cylinders, with india-rubber washers M at the back. The object of this arrangement is to insure that all the products of combustio11 be effected by means of catches or stops actshown in Fig. 5, air and gas will pass through ing l,'to which piece is attached the rod K,

shall be forced out from between the pistons B and'F F,an'd that the latter'shall fit close 1y against the former while performing their stroke, l

Instead of arresting-the motion of the loosepistons'by' the rod G, as described, this may uated by the engine-shaft, (or by the; stem of the'admission'valvesg soaszto project through the side otthe cylinderat the required time and place,'and"thus stop theloosepiston; As

I have before stated, the packing of the'loose pistons F F operates in aid of the packing of th'episton B, astheyfollow the latter closely While it performs its stroke, and, as accuse q'uence of this, it will be evident that the operation of the enginemay be modified by malting the piston '15 to Work loosely or without packing, acting simply as a=disk,- the loose pistons being made to' act' alternately as the Working pistonin pressing againstthe piston" or disk B, when caused to perform their stroke by the atmospheric pressure, and thus impart ing motion to the engine-shaft through the Piston-rod B"; h The construction ofthe valve-gear I I for admitting the chargeof 'combustible gas and air into the cylinder, and the arrangement for igniting the charge, areshown atFigs. 5 and 6', which show, respectively, an} enlarged lon gitud-inal section and a'transverse section on' line Z Z, ofthevalve-gear. The valvecasing I communicates with the cylinder-port H by a passage, 1, opening'into the chamber i In this chamber is a conical 'valve, 11 fitting against a seat, 11 and having; a stem,- i ,of large diameter, passing through j 'a second chamber, 11 in the valve -casing, and 'out through theend'thereot'. The stem i has a central passage,'i passing'right through it, which serves for the admission of atmospheric air, and round this are'iormed a number of small passages, i communicating at the one end with an annular passage, 77, which is connected by a'nozzle, i to a flexible gas supply' pipe. At the other end 'thepassagest' open into the open face'of the 'conical valve-i Thus when the valve is away from its seat, as

the passages and i into the chamber z' whence the explosive mixture will pass into the cylinder; but when'the valve is closed the supply of'ga'san'd air-"will be simultaneously cutoif.

The valve is actuated in the following main: her: It is connected by bars 0' with a piece, 11, working air-tight in the front end of cas that receives motion from the cam E on the engine-shaft. Upon this rod is an adjustable nut, is, and plate 10, against which presses a" spiral spring, k that abuts against a shoul 'der on the valve-casing' Thus the rod K, being acted upon by the cam E pushes the valve open at the proper time for the admission of air and gas, and on the nose of the cam leav ing the end of the red the spring 10 acting thence throu therein." I

more or less on the rod K, so 'a's to regulate the pressureof the springi In the'hottomofi' the chamber 11 1s a gasjet, i ,kept constantly 1 burning, which is supplied with air through the hole i in the casing, whilea chimney, i 35 isprovided at the top of the chamber z'flto promote 1 a draft for the flame,'- which plays, ;round the stem 2' of the valve. f-The yalve t jis'formed with a cylindrical part','which,-whe u it is open, fits into a circular'opening, i betwee'u the chambers i and 6 and, thus shuts of the com munication between these cham-f bers'through such opening; As thewalve closes it uncovers this opening, and ratthe :same time thedisk-t' formed on the-"stemflifl ';in advancing 1apidly, 'col1yeys a'portion at %the flame that is playing round thestem in the chamberi, through the opening t -iinto the chamber i and then closes the co'mmun i cation betwee'n 'i and 11 again byfitting with" a beveled rim against the beveled face 2'". "At" the same time the'flame' carried into i passes gh the openingijand port into the cylinder, and ignites the explosive charge The'power of the engine is"reg ulated by a governor in s'uch'a manner that'shouldt-he' speed of theengine be too great the supply-0E combustible gas is entirely cut'ofiIand theworking piston consequently pertbrms it's strokes Without any explosion ofgas and airy takin gplace, n ntil bythe reduction ofth'e' speed s the'gas-supply is again fully opened, so that the proper proportions of combustiblegasand air, and the quantity of the mixture requiredfor each'eiqilosivecharge in order to produce; the best-results, having been'determined, these proportions and quantity are'not in any way Zvaried for increasing or decreasing the power of'the engine. 1 The arrangement forthis 'pnr ,pose willbe understood 'on"referenc e to Figs; 7 and 8, which show, res .)ectively, an enlarged? transverse section andpart' longitudinal seetion of the engine-shaft, with the regulating- "uiechanism.

- ()0 is the supplypipe for combustible'igas'g which is connected "by flexible tubes to the nozzles i on the admission-valve,ems-before described. Th'e'gas passes from "into 0 on its way to the engine, as indicated by the a'r row. Over the mouth of the pipe ;O "is a valve, P, attached toa s 'iindle, P ,'p'assing through a stufling-box'on the pipe, and car-f ried externally by a thin steel plate, Q fitting into a neck on the spindle, as show-n, and connected to'the arms of the governor-balls'Q.-

These are carried by brackets projecting from a sleeve, Qfi-which rotates upon'the cylindricz'tlf g1and'O carrying with it the go\-'ernor=balls,: such rotation being effected by a bevel-pin'io'n,': Q fixed to thesleeve QZa-nd in gear with the bevel-wheel R. fixed on the engine-shat't E. The spindle P, which does notn'e'volve with the governor, passes through thepinion,"

the: engine cylinder.

and',being extended upward somewhat, is provided at its end with a head,'P This head 7,

projects laterally, as shown, so as to pass over or under two projections, R R, formed on the face 1 of the wheel R. The head 1P isform ed with a feath er-edge presented toward afeatheredge formed o'nff the projections It, and these are formed with inclines, asshown.

' From this will-be seen that if, while the engine is running at its normal -speed, the governor-balls are adjusted so as to hold the spindle-with its head at such a height that its feather-edge is just above that of the projectionsR, these, in rotating, will pass underneaththe head, and will thrs keep the valve Braisedfull open during the intervals when aeharge of gas and air has to be drawn into Oftheengine is slightly increased, the gov-- ether-will cause the spindle P to be slightly depressed, whereby the feather-edge of P willbebrought slightly below the feather-edge Ofs-R, andconsequently the inclined surface of thelatter, in passing over the head 1?, will press down the spindle P and will consequently close the valve P, thus entirely outtingoft' thesupplyof gas during the time that the admission-valve of the engine is open.

Thus it willbe seen that the governor only serves to bring the mechanism into action for cutting off: the gassupply, so that a very slightincrease of speed beyond that required at once .causes the gasrsupply to be entirely cut off, as abovedescribed.

Inthe gas-supply pipe O'is a flap-valve, S, which is kept open by a weight, S, that can be screwed more or less through the valve, andothus by shifting its center of gravity, regulate theextent to which it is kept open.

The'object of thisvalve is to prevent more than the regulated quantity of gas for each charge fromentering the cylinder, as, should byany chance the loose piston, in following the working piston,.stick in the cylinder beforecompleting its stroke, and. thus-cause an increased suction to takeplace in the cylinder by reason of. the greater space that would be formed between the loose piston and the working piston, then such increased suction, in drawing the gasfrom the right-hand side of the-valve S quicker than it could flow past the valve, would cause the valve to be more orlessclosed by the pressure behind it, so as to throttle the gas-supply.

As before stated, it is proposed to work the engine either by ordinarycoalgas or by bydrocarbon or petroleum vapors;

-1f coal-gas is employed, it enters the pipe O'through the branch 0 shown in dotted lines in Fig. 1, leading from any convenient point of supply, and passes thence through the pipe 0 0 passing along the cylinder, either inside the water-jacket thereof, as shown, oroutside the, same, and provided with two branches, by which it is connected, by means of lengths of flexible tubing 0 0 to the nozzlesi? on the admission-valves I 1..

If, however, the speed condensed on their passage through the flexiround the valve-stem i.

If the engine is to be worked by petroleum vapor, the liquid petroleum is introduced in a small stream into the funnel-mouthed opening T of a pipe, T, that passes along the cylinder inside the water-jacket, at the end of which it communicates with the pipe 0, as shown at Fig. 1. The small stream of liquid petroleum in flowing along the pipe T will become volatilized by the heat of the water in the water-jacket, and, mixing with acertain quantity of air,-that also enters the unnelmouth T, will flow through the O to the-admission-valves I I. The volatiliz ation of the whole of the petroleum i's still further insured by the additional heating it, obtains on its passage through the pipe 0 inside the water jacket, and should any particles escape perfect volatilization, or become reble pipes O 0 into the valves I 1, they will become vaporized on their passage along the channels i by the heat of the flame i playing The flame i may in this case be supplied from a special petroleum-lamp, or from ordinary coal-gas. Although a certainamount of air will be mixed with the petroleum vapor, as described, yet a further air-supply will be required for the explosive charge, and as in this case it will be necessary also to heat such air-supply before it mixes with the petroleum vapor, I introduce it through an opening, U in the cylinder-jacket, Fig. 2, into a pipe, U, inside the 'acket, where itbecomes heated, and whence it is led, through flexible tubes U to the end of the passages 47 of the admission-valves. Here the air also becomes further heated. by the flame 3 By causing the air and gas to pass through pipes in the water-jacket so as to take up heatfrom the water, as described, the advantages will be gained that, first, a saving of heat, otherwise lost, will be effected; and, secondly, the quantity of cold water required will be reduced in consequence of the refrigerating action produced by the evaporation of the petroleum upon the water. The volatilization of the liquid petroleum might also be effected by conducting it through small pipes inside a chamber, into which the hot products of combustion are made to issue from the passages L, or by causing the products of combustion to passover the exterior of and through pipes in a chamber containing porous material saturated with petroleum.

For effecting the circulation of water through the working piston and piston-rod, as before mentioned, the following arrangement is empipes O and opening in the end of the water-jacket A v comes in contact with the side of the receptacle V whereby the valve is forced from its seat,'th usallo\ving a certain quantity ot'..water to flowfrom the water-jacket into the re ceptacle, whence it passes down the branch V pipe V, and branch V into the piston. At the same time .water escapes from the piston at top through the pipe V into the space in the hollow piston-rod surrounding the pipe V, flowing to the front end of the piston-rod,

and escaping, through the outlet V into a trough, V that conducts it away. Cold wa ter' is supplied to the water-jacket A through the pipe A Fig. 4; I

When the receptacle V moves away -from' the valve W on the piston B beginning its forward stroke, the valve is closed by means ofa spring, W n

Having thus described the nature of my invention, and in what manner the same is to be performed, I claim- 1. A double-acting gas-engine, wherein a partial vacuum is formed by the expansion and cooling of the products of combustion alternately on each side of the workingpiston, the atmospheric pressure on the other side of the piston producing motive power, substantially as herein described. v

2. A double-acting gas-engine consisting of a cylinder open at both ends to the atmosphere, and having a working piston, on each side of which is a loose piston, so arranged that at the end of each stroke the .one loose piston, by the explosion of a charge, is propelled to the end of the cylinder without doing work, and is held there while the gaseous products of combustion contract, and the working pis ton, together with the second loose piston, is caused by atmospheric pressure to perform its stroke, substantially as herein described.

3. In a doubleacting gas-engine, the cylinder A, with splayedopen ends A operating in combination with the working piston B and two loose pistons, F F, having conical segment -rings f substantially as herein described.

4.. In a double-acting gas-engine, the loose' pistons F F, and a device for arresting the motion of said pistons to form a space for the explosive gas, operating alternately in combination with the piston B as working pistons, substantially as herein described.

5. In a doubleacting gas-engine, the method v of effecting thesimultaneous expulsion of the products of combustion on one side of the working piston, and the drawing in of an explosive charge on the other side of the piston, substantially as herein described.

6. In a double-acting gas-engine, the working piston B with rod G, operating in combination with the loose pistons F F in such manner that, as the piston B toward the end of its stroke approaches the one loose piston, so as to expel the products of combustion, the drawing in of the next explosive charge is simultaneously efi'ected by arresting the mo- 7. In a gas-engine, a loose piston propelled by the explosion, in combination with degvi ces for wedging saidpiston, whereby it is heldat the end of its stroke by absolute counter-pressure exerted thereon by'the' c 'yIimIer-surtace, as distinguished froin mere frictional contact, substantially as herein described. V

8. The loose 'pistoiiF with cylindrical part f fitting with packingf against the cylinder, and coned part f with conical segment-ring f controlled by springs f and operating, in combination withthe coned -ends A of'the cylinder A, substantially as herein described.

9. In combination with the loose pistons, a broad ring of leather or other material, f held at its middle by a ring,f, so that while the piston can move loosely in the cylinder, the pressure acting on the leather ring on the one side or the other of the piston will insure its working air-tight, substantially as herein described.

10. In combination with the loose pistons and the segment-ring for wedging the same in the cylinder, a device or devices for releasing the loose piston when pushed by the working piston, substantially as described.

11. The yielding annular buffer-plates M, operating, in combination with the pistons F, for efl'ecting a close contact between them and the working piston, substantially as herein described.

12. The method of regulating the power of i gas or petroleum engines by entirely cutting off the supply of combustible gas or vapor when the engine is running above its normal speed, while the working piston remains continuously in motion, substantially as herein described.

13.. The combination of a governor, the valve of the gas-supply-pipe, and suitable intermediate mechanism for causing the governor to fully open or close the gas-supply, whereby a uniform quantity of gas for each charge is insured, substantially as herein described.

14.. The valve P with stem P and head. P operating, in combination with the governor Q and projection B, so that the governor only serves to bring parts into action, whereby the gas-supply is either entirely closed or fully opened, substantially as herein described.

15. In combination with the gas-supply pipe of a gas or vapor engine, the flap-valve S, provided with an adjustable weight, S, substantially as and for the purpose specified.

16. The admission-valve apparatus I, with inlets for both gas and air formed in the valve and valve-stern itself, and so arranged that by the closing of the valve the gas and air supply are simultaneously cut oft, substantially as herein described.

17. In admission-valve apparatus to gas or petroleum engines, the gas-jet a" burning in the chamberi, with air-holes 6 and chimney 1 the said gas-jet being made to ignite the -geh-ai'ge in the: engine-cylinder by causing a poi-rion of the fiame to be conveyed by-means 'ofithe disknl into the, valve-chamber, subfiedr i -::'20. 'lheihollow-piston'B and piston-rod B, supplied withwater from the water-jacket of the cylinder by the valve W, receptacle V and pipes V V V, substantially as herein described. 1 I

21.,The-donb1e-acting gas or petroleuml enginer consisting of the cylinder A, pistonsB F F, admission-valves I l, and regulatingvalve P, all combined and operating as herein described. I In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses this llth day of March, 1875. t

GOTTLIEB' WILHELM DAIMLER.

Witnesses:

HENRY HijLsoHER, EMIL LEHMANN. 

